Rumors of Bergdahl's return to duty come in the midst of months of accusations and speculation over whether he deserted the military before being captured. Bergdahl was traded for five Taliban prisoners after spending five years in captivity. But his rescue was marred by accusations that he deserted the Army prior to being captured and didn't justify the trade.

There have also been doubts cast on whether he ever should have joined the army at all. The Washington Post reported in June that Bergdahl was discharged from the Coast Guard for "psychological reasons" months before enlisting in the Army, and friends said they were surprised the army accepted him.

News reports are focusing on the Germanwings pilot's possible depression, following a familiar script in the wake of mass killings. But the evidence shows violence is extremely rare among the mentally ill.